Controlled Substances

1. Controlled Substances Forensic Science

2. Drug Dependence • A drug is a natural or synthetic substance that is used to produce physiological or psychological effects • An illicit drug is an illegal substance • Controlled substances are those administered only with a doctor’s prescription

3. Drug Dependence (continued) • Physical Dependence • Physiological need for a drug is • Caused by its regular use • Characterized by withdrawal sickness when administration of the drug suddenly stops • Some of the more widely used drugs have little potential for physiological dependence • Physiological dependence develops when the user has a regular schedule of drug intake

4. Types of Drugs • Narcotics • Drugs that induce sleep and depresses vital body functions such as blood pressure, pulse, and breathing • Opiates come from the Asian poppy • Includes heroin, morphine, and codeine • Considered analgesics (substances that lessen or eliminate pain)

5. Types of Drugs (continued) • Narcotics (continued) • Synthetic Opiates • Methadone • Pharmacologically related to heroin • Oxycontin(oxycodone) • Closely related to morphine and heroin • Prescribed by doctors for chronic pain

6. Types of Drugs (continued) • Hallucinogens • Drugs that can cause alterations in normal thought processes, perceptions, and moods • Marijuana • The most widely used illicit drug in the U.S. • Derived from the cannabis plant • Leaves, flowers, stems, and seeds are mixed in varying proportions • Contains tetrahydrocannabinol(THC)

7. Types of Drugs (continued) • Other hallucinogens • Psilocybin (mushrooms) • LSD (lysergic acid) • PCP (phencyclidine)

8. Types of Drugs (continued) • Depressants • Drugs that slow, or depress, the central nervous system (CNS) • Alcohol • With more production and more consumers, alcohol is unquestionably the most widely used and abused drug • Effects range from inhibited judgment and concentration in low doses to extreme irritability, or even coma, and possibly death in extreme doses

9. Types of Drugs (continued) • Depressants (continued) • Barbiturates • Commonly known as “downers” because they relax the user and may produce sleep • Some examples that are commonly used in medicinal practices are • Amobarbital • Secobarbital • Phenobarbital • Methaqualone(aka Quaalude) is an illicit barbiturate

10. Types of Drugs (continued) • Depressants (continued) • Antipsychotics and anti-anxiety drugs • Produce tranquility without altering higher level thinking faculties • An example that is commonly prescribed to deal with everyday tensions is • Diazepam (valium)

11. Types of Drugs (continued) • Depressants (continued) • Huffing/Inhalants • Sniffing volatile solvents such as model cement, glues, and cleaners • Inhaling aerosol propellants such as spray paint and Freon • Produce feelings of exhilaration and euphoria, then drowsiness and stupor

12. Types of Drugs (continued) • Stimulants • Stimulate, or speed up, the CNS • Amphetamines • Known as “uppers,” or speed • Produce increased alertness and feelings of well-being followed by a decrease in fatigue and loss of appetite. These are accompanied by restlessness, instability, and many times depression

13. Types of Drugs (continued) • Stimulants (continued) • Cocaine • Comes from the “coca” plant in tropical Asia and South America • Has effects similar to amphetamines • It is very difficult to overcome addiction to this drug

14. Types of Drugs (continued) • Club Drugs • Synthetic drugs that are often used at nightclubs, raves (all night dance parties), and bars; they are used as a way to stimulate the “rave” experience • GHB and Rohypnol (aka “Roofies”) are CNS depressants often associated with drug-facilitated sexual assaults, rapes, and robberies • GHB can produce dizziness, sedation, muscle relaxation, • Rohypnol can produce loss of consciousness and inability to remember what happened during the hours after ingesting

15. Types of Drugs (continued) • Club Drugs (continued) • Methylenedioxymethamphetamine (aka MDMA or Ecstasy) • Is a mind altering drug that has hallucinogenic effects • Chronic use can cause body system breakdown, severe brain damage, memory loss, and seizures • Ketamine (aka Special K) • Is an animal anesthetic used by veterinarians • However, when it is used on humans, it causes feelings of euphoria, visual hallucinations, impaired motor function, and amnesia

16. Drug Control Laws (continued) • Schedule III • Less potential for abuse, currently accepted medical use, potential for low to moderate physiological and high psychological dependence • All barbiturates not included in Schedule II, such as codeine preparations and anabolic steroids

17. Forensic Drug Analysis: Screening and Confirmation • Screening test – a preliminary test used to reduce the number of possible identities of an unknown substance • Confirmatory test – a single test that specifically identifies a substance • Color test – drugs yield characteristic colors when mixed with certain chemicals

18. Forensic Drug Analysis: Screening and Confirmation (continued) • Color test – drugs yield characteristic colors when mixed with certain chemicals

19. Forensic Drug Analysis: Screening and Confirmation (continued) • Microcrystalline Test • More specific than a color test • Identifies a substance based on the color and shape of crystals formed when the substance is mixed with specific reagents

20. Forensic Drug Analysis: Screening and Confirmation (continued) • Chromatography • Separates complex mixtures into specific components by an attraction to a stationary phase while being propelled by a moving phase • Thin Layer Chromatography uses a solid stationary phase and a moving liquid phase; can be used to compare an unknown sample with known samples

21. Collection and Preservation of Drug Evidence • Packages must prevent loss and cross-contamination of evidence • If it is a volatile solvent (glue sniffing compounds), it must be in an airtight container to prevent evaporation • Mark with information to ensure identification by the officer and maintain a chain of custody • The investigator should provide any background information of the drug’s identification, such as the screening tests, to the lab analyst